The present invention relates to a self-traveling vehicle which can travel by itself without guide wire or cable, based on positional information detecting a current position and map information indicating a traveling road or path.
Previously, there is described in Japanese Unexamined Patent Publication No. 148245/2000 a caddie cart which can travel along the pre-determined road by detecting magnetic field from the guide wire buried in surface along the road.
However, there are problems in the above-mentioned cart system. In a facility (e.g., golf course) where such a self-traveling vehicle travels, the system necessarily requires a construction of the guide lane such as guide wire. It results in a cost increase. Further, when a traveling course is to be changed, the system requires also a change of the course of the guide wire buried in road surface. It takes labor and expense so that such change of the traveling course is not easy.
The present invention is carried out for solving the above problems. An object of the present invention is to provide a self-traveling vehicle without requiring guide wire for travel, accordingly it is possible to change a course easily without expense or labor of the construction. Another object of the present invention is to provide a self-traveling vehicle which is safe and convenient to user.
In order to achieve the above-mentioned object of the present invention, it is preferable that a self-traveling vehicle comprises a traveling drive circuit for driving a drive source, a steering wheel drive circuit for operating a steering wheel and a receiving means for receiving signals of positional information from a satellite,
wherein said self-traveling vehicle comprising,
a calculating means for calculating current positional information based on the signals transmitted from the receiving means;
a storing means for storing a traveling road to be traveled, which is set beforehand;
a controlling circuit for controlling the traveling drive circuit and the steering wheel driving circuit in such a manner as to travel on a predetermined set road by verifying the current positional information calculated by the calculating means and the road to be traveled stored in the storing means.
More preferably, traveling directions to be traveled on said traveling road and a layout of a golf course are stored in said storing means.
More preferably, an information of said traveling road and a positional information calculated by said calculating means, both of which are stored in said storing means are displayed on a display.
More preferably, the self-traveling vehicle further comprises a braking means for braking a movement generated by said drive source and a detecting means for detecting a direction in which the self-traveling vehicle travels,
said movement is braked by said braking means when the self-traveling vehicle travels in a direction opposite to a stored direction stored in said storing means after said direction is detected by the detecting means.
More preferably, said detecting means calculates a deviation departed from said stored direction based on a position of the self-traveling vehicle within a predetermined time period.
More preferably, said direction in which the self-traveling vehicle travels is detected by the detecting means using a traveling locus.
More preferably, the self-traveling vehicle further comprises a detecting means for detecting a direction in which the self-traveling vehicle travels and a steering direction detecting means for detecting a direction in which said steering wheel is operated,
wherein said positional information is prepared after failing to detect a positional signal to be transmitted from the detecting means and the steering direction detecting means if the positional information is not received by the receiving means,
whereby the self-traveling vehicle travels based on the prepared positional information and the traveling road stored in the storing means.
More preferably, the self-traveling vehicle further comprises a velocity detecting means for detecting a velocity of the self-traveling vehicle;
wherein the more said velocity increases, the more a frequency of reading said positional information from said calculating means implemented by the controlling circuit within a predetermined time period increases.
More preferably, the controlling circuit operates the steering wheel driving circuit using a forward position having a predetermined distance calculated by the calculating means as a target.
More preferably, said controlling circuit operates the steering wheel driving circuit using said forward position,
wherein the more velocity increases, the farther said forward position is used as a target.
According to the above-mentioned structure, a self-traveling vehicle travels by driving a driving source through controlling a traveling drive circuit and at the same time by determining a travel direction through steering a steering wheel by controlling a steering wheel drive circuit. Further, the self-traveling vehicle receives positional information from a satellite by a receiving means (receiver), calculates a current position by means of calculating positional information, and deduces a current position of the vehicle on the map through combining the positional information with means of storing travel road. Then, a travel direction is calculated by collating the travel road in means of storing travel road with positional information, to control the traveling drive circuit and steering wheel drive circuit so as to travel according to the travel direction in means of storing travel road. Thus, a self-traveling vehicle travels in an indicated direction by subsequently collating the positional information by means of calculating positional information with travel road by means of storing travel road.
Further, in addition to a travel road, a layout of a golf course is stored in means of storing travel road, thereby, such self-traveling vehicle can travel along the golf course. Such information is displayed in a display screen such as LCD provided in the self-traveling vehicle, which can show players the current traveling position in a golf course.
Furthermore, when by means of calculating positional information, a current travel direction is determined to be opposite to the direction stored in means of storing travel road, a drive to drive means for traveling is stopped and travel is stopped by braking means. Thus dangerous travel can be stopped. One method to determine to be the opposite direction is to compare travel positions between the predetermined time interval and to determine the travel direction. If travel direction is opposite to what is predetermined, the vehicle is decided to travel backward and stopped. Other method to determine to be the opposite direction is to compare the locus of travel and the current direction of the travel and to calculate the direction relative to that stored in means of storing travel road so that whether the direction is forth or opposite is decided.
Further, when a receiver cannot receive a satellite signal due to a poor condition for receiving electromagnetic wave or a signal line breakage while traveling by means of calculating positional information and means of storing travel road, the current position can be obtained by calculating a virtual position after disappearance of the signal with use of means of detecting direction which detects travel direction of encoder or the like and use of steering direction detecting means which detects steering direction of the steering wheel. By these methods, a current position is assumable even if signal from a satellite can not be received and the current position becomes unclear. Thus, the vehicle can continue to travel without stop.
When a vehicle travels by means of calculating positional information and means of storing travel road, the more velocity of the self-traveling vehicle increases, the more frequently the calculating of the positional information is made within a predetermined time, thereby the vehicle can quickly decide the current position and never runs over the travel road stored in means of storing travel road.
Furthermore, in traveling, the vehicle can travel along the travel road by steering, with use of a forward position having a predetermined distance calculated by the calculating means as a target.
And, since the more the velocity of the self-traveling vehicle increases, the farther the forward position is used as a target for driving the steering wheel drive circuit, the vehicle never runs over the travel course even at a high speed.
In order to achieve the above-mentioned object of the present invention, it is preferable that said controlling circuit stops driving said drive source, when a signal from said receiving means is not received.
More preferably, there are switchably provided a self-traveling mode in which the vehicle travels through said controlling circuit and a manual-traveling mode in which the vehicle travels with steering wheels manually operated by an user,
wherein said controlling circuit switches to a manual-traveling mode if a signal from said receiving means is not received.
More preferably, there is provided a display indicating whether a signal from said receiving means is received or not.
More preferably, there is provided a display indicating a current traveling mode in which said vehicle travels.
More preferably, there is provided a display indicating whether a signal from said receiving means is received or not and a current traveling mode,
wherein if a signal from said receiving means is not received, the display shows that a signal from said receiving means is not received, then if a signal form said receiving means is received the display shows that a signal form said receiving means is received and that a switch to self-traveling mode is possible.
More preferably, said display that a switch to self-traveling mode is possible is indicated only when said vehicle is on the pre-determined road.
According to the above-mentioned structure, when positional signal cannot be received due to bad condition for receiving electromagnetic wave or a signal from receiver cannot be received due to a signal line breakage while traveling, the vehicle is controlled to stop travel. By such control, the vehicle does not run off the traveling road uncontrollably, which improves safety.
Further, when positional signal cannot be received due to bad condition for receiving electromagnetic wave or a signal from receiver cannot be received due to a signal line breakage while traveling, the vehicle is stopped and changed from self-traveling mode to manual-traveling mode. By such control, the vehicle does not run off the traveling road uncontrollably, and users can drive the vehicle in manual mode. Thus, because the vehicle is once stopped and then changed to manual-traveling mode when a receiver can not receive the signal, a safe self-traveling vehicle is realized.
Further, because a presence or absence of the signal from receiver is indicated in a display part, a user can decide whether self-traveling mode is available and convenient vehicle is realized.
Furthermore, because current traveling mode, either self-traveling mode or manual-traveling mode is indicated in a display part, a convenient vehicle is realized.
Moreover, when the signal from the receiver disappears, a message that the signal from the receiver disappears is indicated in a display part, and then in traveling in manual mode, when the signal from the receiver is input, namely reception of positional signal from a satellite is restored, a message that the signal from the receiver is input and an message that a change to self-traveling mode is available are indicated in a display part. Accordingly, a convenient self-traveling vehicle is realized.
Further, a message that a change to self-traveling mode is available is indicated only when the vehicle is on the predetermined traveling road. Therefore, when a change to self-traveling mode is done, the vehicle can travel on the road as it is, and a change of traveling mode can be made smoothly.